The present invention relates to electric stringed musical instruments which generate analog electric signals in response to playing one or more strings of the instrument and which modify the electric signals through an analog circuit mounted on the instrument. It is a particular aspect of the present invention that the analog signal is digitally controlled, preferably such that desired preset conditions for the analog circuit can be stored and later recalled in a simple, rapid manner by a musician while he or she is playing the instrument. Another aspect is to conserve electrical energy when the instrument is operational. Still another aspect is to provide a control signal, such as for use in the energy conservation, in response to movement of at least one of the strings of the instrument.
Although the present invention is applicable to and encompasses any electric stringed musical instrument of a type suitable for the digital control referred to in this specification, it will be described with reference specifically to electric guitars. The term "electric guitar" as used in this specification and in the claims encompasses electric bass guitars, electric lead or rhythm guitars, and any other similar instrument despite any differences such as the number and type of pickup, the nature of the analog circuit through which signals from the pickup(s) are processed, and the type and layout of the controls located on the guitar body and manipulated by the musician.
A conventional electric guitar has a body to which the strings are attached and on which various controls are located. One or more pickups are mounted on the body beneath the strings so that electric signals are generated in response to movement of the strings. One type of pickup is electromagnetic whereby the electric signals are produced in response to string movement through the magnetic field. An analog circuit typically containing one or more resistors and capacitors connects between the pickup(s) and an output jack in which a cord is plugged to connect the analog circuit of the guitar to a preamplifier or amplifier. One or more of these resistors and capacitors has a variable resistance or capacitance which the musician can change by manipulating the controls which are mounted to the guitar body and connected to the variable analog circuit components. This control allows the musician to change the tone (frequency blend) and volume (magnitude) of the electric signals provided to the output jack.
With this conventional analog electric guitar, the guitarist has to manually change the respective control knobs or switches on the guitar body to obtain a desired tone and volume. This can be inconvenient and inexact when the musician has to do this during the course of a live performance each time he or she gets to a musical passage or song that requires the analog circuit parameters to be changed. That is, for a particular passage or song, the musician may know ahead of time that a desired set is to be used; and with a conventional electric guitar, the musician also knows that the desired set will have to be manually input by turning one or more respective knobs or moving one or more switch arms. It would be desirable if such desired settings could be implemented without the musician having to directly make each setting adjustment for all the analog circuit parameters that need to be changed for the desired set, and yet still have the electric guitar otherwise be operated, and sound, the same as the conventional electric guitar. More broadly, there is the need for a digitally controlled analog electric stringed musical instrument that can be operated in a conventional manner and that provides the instrument's conventional sound.